The Microsoft DirectX Software Development Kit (SDK) provides a set of excellent Application Programming Interfaces (APIs), which is able to provide various resources used for developing high-quality and real-time applications and one of the main objectives of which is to promote the development of the games and multimedia applications based on the Windows Operating System (OS). Before the DirectX appears, the main game development platform is MS-DOS, and game developers have to try their best to adapt their applications to various hardware devices. Since the DirectX comes into use, the game developers can not only benefit from the device irrelevance of the Windows platform but also possess the characteristic of accessing hardware directly. The main purpose of the DirectX is to provide an ability of accessing hardware as compact as that of the MS-DOS, thereby implementing and improving the operation effect of the applications based on the MS-DOS platform, and removing the obstacle of the innovation of the personal computer hardware.
On the other hand, the developing DirectX is to provide the ability of accessing the hardware in real time with high expressive force for the applications based on the Windows platform on the current or future computer operation systems. The DirectX provides a set of integral and identical interfaces between the hardware device and the application so as to reduce the complexity of installation and configuration and fully use the excellent characteristic of the hardware. By using the DirectX-provided interfaces, software developer can make the best use of the high capabilities provided by the hardware without worrying about those complicated and changeful hardware execution details.
Despite the advantages of the DirectX mentioned above, most games, currently developed based on the DirectX, are resource-occupying-exclusively software. When the user is playing game, the game interface is displayed in full screen, so that the screen can not be optionally switched to other software interface.
At the same time, it has been the first choice currently for net citizens to play the network online game and chat on the net according to statistics, and most net citizens want to play games and chat simultaneously. However, the current instant messaging tools all adopt the standard Windows mechanism, a window can not be called out in a DirectX game of the full-screen mode, where the user has to switch the game window to the desktop to normally use the basic functions of instant messaging, thereby severely affecting the process of the game contents and even causing the self-quitting of the game. Even though some network online games can provide a chat function, the chat function is only limited to the chat between game players, and the game player can not communicate with other friends except the game players by instant messaging, which can not adequately satisfy the instant messaging demands of the game players.
In a similar way, for other users of the software developed based on the DirectX, there also exists the problem that the instant messaging can not be performed if the software is in use for the reason of it monopolizing the resources.